Clarkey

FWIW I use a Mele Quieter 2 and I added extra nvme for data storage but left the operating system and programs on the existing emmc. Technically it may be better to put everything on a new drive, but I have had no issues running 2 x NINA with PHD2 on my dual rig. If it ain't broke.....

How about a 115mm triplet such as a TS photoline? There are a number of 'clones' too. Probably the limit for an HEQ5 but could be used at native FL or with a reducer.

It's astro gear. What do you expect?😆

I have 2 Baader ST's, one on my 6" f4 Newtonian and one on my RC8. I found them to be excellent for imaging. With regards to the scope collimation, the f4 is a right PITA to collimate. I share your pain. However it is much better with a good focuser - the original TS one was pretty awful. Maybe avoid the laser if you are struggling with it?

I used to use a 12v powered hub on my mount, chopping off the 240v plug and replacing it for a 12v. This was connected to an active cable. https://www.amazon.co.uk/RSHTECH-Powered-Extension-Charging-Individual-Red/dp/B07RS31T3Y/ref=sr_1_9?crid=1BHL2DWLICKVV&keywords=12v+usb+hub&qid=1658258974&sprefix=12v+use+hub%2Caps%2C147&sr=8-9 Most of the time it was OK but it did get temperamental with my ASI1600. Eventually I changed to a mini PC on the mount (Mele Quieter 2) which I should have done from the start. Works very well and no connection issues.

Looking at the image above suggests it is more than just distance from the sensor - possibly some tilt as well. The star shapes are certainly not consistent with purely a back-focus issue. If it is was purely distance all of the stars would be pointing away from centre or around the centre - but this is a mixture.

From my experience of the RC8 I found collimating the secondary worked well with the TS collimator (even though it is the world's most expensive LED light with a hole in). Following this I use a star test to get the primary aligned. Whether this is the 'right' way is another question but it works for me. I have tried some other methods including the laser version which completely ruined my relatively good collimation. Once right I think they are excellent imaging scopes.

I have used a similar system to Budgie1 above without a problem. (The asi1600 was temperamental with the hub but the cable was ok). You can get 12v powered hubs which make it easy to use a standard astro supply. I have now converted to a Mele Quieter 2 mini PC at the mount for convenience which is just easier for me.

I have not used the 2" version but the 7/8 position wheel I have has been absolutely fine. I am not aware of any specific issues with the larger wheel but I am guessing most of the control is pretty the same. I do multi filter imaging and flats without a problem.

I would suggest if you are struggling to balance the scope the axis are too stiff. I would recommend a strip down and regrease to loosen the whole thing. My HEQ5 was stiff (but not that bad) but is now very smooth and easier to balance. I would also add that if the axis is that stiff the guiding will undoubtedly be affected also.

You should be able to go into the handset and reset the NPE value to 0 in the settings menu.

I am happy to use a bahtinov mask if necessary, but statistical measurement is easier as I am always connected to a screen. I generally get the same result either way.

I'm glad I'm not the only one.....😂😂

A couple of things come to mind. Firstly, I assume the sensor distance from the camera front to the sensor is the same for the ASI and QHY? In theory the focus point with the same kit should be at the same place so the 20mm difference does not make sense. Secondly the star shapes seem to be getting worse as the distance increases (although I am looking on a small screen). Are you sure it does not need to be closer? Probably not much help, but it is all I can think of.

I struggle to track the moon so I am suitably impressed. That is truly excellent.

I agree that the dithering frequency needs to increase. Every 10 frames is only 6 times in the hour which will not be enough to 'staitstically' remove the noise. You could adjust the clipping algorithm but you will probably start loosing detail.

Keep her away from your scope🤣 Looking at the image I would say there are two things that will improve your guiding. Firstly a bigger and better mounted guidescope to ensure no flex. Secondly adjust the mount to get the RMS down.

They do quote 'with accessories' which I assume is finder, diagonal and eyepiece plus tube rings and dovetail.

Skywatcher Website quotes 5.1kg for the OTA. Add a bit for the tube rings gives about 5.5kg. The ED80 is given as 2.5kg. Sky-Watcher | Sky-Watcher Global Website (skywatcher.com)

With regards to the star shapes this does look like a guiding issue. The RMS you are getting is not very good for an HEQ5 - it should be well under 1. The Rowan upgrade will help, specifically if there is significant backlash, but I do find my HEQ5 does require regular 'tweeking' of the worm drive to keep the guiding to its optimal. The end float on the bearings is also critical. I think you need to get this better before going to OAG as you may end up with the same problem. As for the black mark - this definitely looks like dust/dirt close to the sensor - probably on the sensor glass.

It is towards the top end but I think it should be ok. The ED120 is about 5.5kg and the HEQ5 is probably ok up to 10kg or so. Providing the other kit is not too excessive I don't see it struggling. Having said that I would say a shorter FL may be a better starting choice of AP. Maybe start with your initial choice and consider buying a small refractor at a later date for imaging.

Unmounted filters are just glass. You need a frame to hold them in the EFW. Mounted are screw fitting with an outer metal ring. You won't need to use a uv/if filter with the other filters. You only need this for some OSC cameras and for luminance data. This is basically what the standard ZWO luminance filter is. You can get away without LRGB but most people use these for true star colours. With NB you cannot get accurate stars.

This is very true, especially if you are using 31mm unmounted filters. If your budget won't stretch to the 8 position wheel, the 1.25 mounted filters would be more user friendly to swap. However, the 31mm do allow slightly larger sensors. FWIW I have the 1600mm pro and I have been really pleased with it. Flats are easy and amp glow is easily calibrated out. It is 'old tech' now but still very capable. I have recently purchased a Rising Cam IMX571 colour camera to complement the mono camera. (Could be an option for you?). I'll be using the 1600 for luminance data and the 571 for colour on a dual rig. Ultimately any of these choices will give you good results, but if it was me I would start with the mono route. Personally I find the processing no harder than colour and you get the option of true narrowband imaging.

FWIW I use the DSI collimation method with a REEGO collimator for the secondary mirror. RC collimation is known to be tricky and it took me a call while to get the best method for my RC8.

The ED80 is a very good starter scope for imaging. There is a small amount of CA which can be removed in processing or you can use an L3 filter to reduce it. The focuser is OK, but some people have struggled with it for AP.